The manufacture of products from lignocellulosic natural polymer materials typically proceeds from a wet state through a moist state to a dry product. For the largest volume products made mainly from lignocellulosic materials, i.e. paper and paperboard, there have been numerous developments with the objective of improving the properties and reducing the cost of production. However these earlier developments for manufacturing paper have concerned major changes of the pressing process in the press section, or of the drying process in the dryer section, or of the calendering process in the calendering section. These major changes typically involve undesirable time and cost factors.
Therefore, there is a need for improved methods of processing lignocellulosic materials which overcome or reduce at least some of the above described problems.
Thus the present invention is not a water removal process, is not a drying process, is not a calendering process, being instead is a unique process which is not an element in current sheet or papermaking manufacturing processes. The present invention is a new process involving rapid warming of a moist sheet with the prime objective not for water removal, not for drying, not for calendering, but to improve properties of the material.
Processes for the manufacture of products incorporating lignocellulosic materials normally take place in equipment open to air. A fundamental characteristic is that the temperature of wet or moist material passing through equipment open to air must approach a dynamic equilibrium temperature termed the ‘wet bulb temperature’ or ‘adiabatic saturation temperature’. For this reason, with the air conditions typical in the manufacture of products from lignocellulosic materials, the temperature for the wet or moist material in contact with air is therefore generally in the low range of about 40°-70° C.